現有中文條目：https://zh.wikipedia.org/wiki/生育控制
因為部分條目已經進行過翻譯，有部分中文更新勘誤請更新於此。
例：
英文引言https://en.wikipedia.org/wiki/Wikipedia:WikiProject_Medicine/Translation_task_force/RTT/Birth_control
Birth control, also known as contraception and fertility control, are methods or devices used to prevent pregnancy.[1]Planning, provision and use of birth control is called family planning.[2][3] Safe sex, such as the use of male or female condoms, can also help prevent sexually transmitted infections.[4][5] Birth control methods have been used since ancient times, but effective and safe methods only became available in the 20th century.[6] Some cultures deliberately limit access to birth control because they consider it to be morally or politically undesirable.[6]
’’’避孕’’’或’’’生育控制’’’是避免[[懷孕]]的行為。計畫、提供避孕方法，和使用避孕措施則稱之為[[家庭計畫]]、[[安全性行為]]，像是使用男用或女用保險套，能預防性病的傳染。各種避孕措施從古代就開始被使用，但有效和安全的避孕方法則是到二十世紀才開始變得普及。有些文化謹慎的限制人們避孕，因為他們認為避孕是違反道德倫理或不被官方所接受的行為。
The most effective methods of birth control are sterilization by means ofvasectomy in males and tubal ligation in females, intrauterine devices (IUDs) andimplantable contraceptives. This is followed by a number of hormonal contraceptives including oral pills,patches, vaginal rings, and injections. Less effective methods include barriers such as condoms, diaphragms and contraceptive sponge and fertility awareness methods. The least effective methods are spermicides and withdrawal by the male before ejaculation.Sterilization, while highly effective, is not usually reversible; all other methods are reversible, most immediately upon stopping them.[7] Emergency contraceptives can prevent pregnancy in the few days after unprotected sex. Some regard sexual abstinence as birth control, but abstinence-only sex education may increase teen pregnancies when offered without contraceptive education.[8][9]
最有效的避孕方法是結紮，也就是男性的輸精管結紮手術和女性的輸卵管結紮手術。其次是各式各樣的賀爾蒙類避孕措施，像是口服避孕藥、避孕貼片、陰道避孕環，以及賀爾蒙注射劑。效果較前面兩種避孕措施略低的是屏障法，像是保險套、避孕隔膜、避孕海綿，還有安全期避孕法。而效果最低的是殺精劑和男性性交中斷法。結紮的效果雖然最佳，但是是不可逆的手術。其他的避孕效果皆是可以逆轉的，大部分在停止使用的時候即失去避孕效果。事後避孕措施則是在沒有避孕的性行為數天後使用，以預防懷孕。有些人會認為禁慾是一種避孕措施，但相較於完整的性教育觀念，只強調禁慾的性教育反而會因為服從性不高而增加青少年懷孕的機會。
In teenagers, pregnancies are at greater risk of poor outcomes. Comprehensive sex education and access to birth control decreases the rate of unwanted pregnancies in this age group.[10][11] While all forms of birth control may be used by young people,[12] long-acting reversible birth control such as implants, IUDs, or vaginal rings are of particular benefit in reducing rates of teenage pregnancy.[11] After the delivery of a child, a woman who is not exclusively breastfeeding may become pregnant again after as few as four to six weeks. Some methods of birth control can be started immediately following the birth, while others require a delay of up to six months. In those who are breast feeding progestin-only methods are preferred over combined oral contraceptives. In those who have reached menopause it is recommended that birth control be continued for one year after the last period.[12]
青少年懷孕容易有較多的併發症。完整的性教育和容易取得的避孕措施能降低這個年齡群的意外懷孕率。雖然青少年可以使用各式各樣的避孕措施，但長效型可逆避孕措施對降低青少年懷孕特別有效，像是皮下植入避孕棒、子宮內避孕器、陰道避孕環等等。在生產後，若女性沒有持續無間斷地哺乳，即有可能在生產後四到六個禮拜懷孕。有些避孕措施可以在生產後立刻開始，而有些則需等到產後六個月才能開始使用。對正在哺乳的女性而言，僅含黃體素的避孕措施則是比複合型口服避孕藥（含有雌激素和黃體素）更佳的選擇。對於已經停經的婦女，避孕措施可以持續使用到離最後一次生理期的一年後。
About 222 million women who want to avoid pregnancy in developing countries are not using a modern birth control method.[13][14] Birth control use in developing countries has decreased the number of maternal deaths by 40% (about 270,000 deaths prevented in 2008) and could prevent 70% if the full demand for birth control were met.[15][16] By lengthening the time between pregnancies, birth control can improve adult women’s delivery outcomes and the survival of their children.[15] In the developing world women’s earnings, assets, weight, and their children’s schooling and health all improve with greater access to birth control.[17] Birth control increases economic growth because of fewer dependent children, more women participating in the workforce, and less consumption of scarce resources.[17][18]
在開發中國家裡，約兩億兩千兩百萬想要避免懷孕的女性沒有使用現代的避孕措施。使用避孕措施讓開發中國家的孕婦死亡率降低了40%（在2008年預防了270,000名死亡）。若人人對避孕的需求皆獲得滿足，則可以降低70%的孕婦死亡率。藉由延長該次懷孕與下一次懷孕之間的間隔時間，避孕能減少成年婦女的生產併發症，並提高新生孩童的存活率。在開發中國家裡，能取得避孕措施的婦女無論是收入、資產、體重，以及孩童的就學和健康，皆獲得改善。避孕能增加經濟成長，因為能讓更多的婦女就業，減少需要撫養的孩童，並且能減少早已匱乏的資源的消耗。
Contents [hide]
| Method | Typical use | Perfect use |
| No birth control | 85% | 85% |
| Combination pill | 9% | 0.3% |
| Progestin-only pill | 13% | 1.1% |
| Sterilization (female) | 0.5% | 0.5% |
| Sterilization (male) | 0.15% | 0.10% |
| Condom (female) | 21% | 5% |
| Condom (male) | 18% | 2% |
| Copper IUD | 0.8% | 0.6% |
| Hormonal IUD | 0.2% | 0.2% |
| Patch | 9% | 0.3% |
| Vaginal ring | 9% | 0.3% |
| Depo Provera | 6% | 0.2% |
| Implant | 0.05% | 0.05% |
| Diaphragm and spermicide | 12% | 6% |
| Fertility awareness | 24% | 0.4–5% |
| Withdrawal | 22% | 4% |
| Lactational amenorrhea method | 21 | 22 |
使用於第一年的懷孕率
避孕措施 典型使用 完美使用
無避孕
複合型口服避孕藥
黃體素口服避孕藥
女性結紮
男性結紮
女用保險套
男用保險套
銅T型子宮內避孕器
賀爾蒙子宮內避孕器
避孕貼片
陰道避孕環
賀爾蒙注射劑 (Depo Provera)
皮下植入避孕棒
避孕隔膜和殺精劑
安全期避孕法
性交中斷法
泌乳停經法
Methods
Birth control methods include barrier methods, hormonal birth control, intrauterine devices (IUDs), sterilization, and behavioral methods. They are used before or during sex while emergency contraceptives are effective for up to a few days after sex. Effectiveness is generally expressed as the percentage of women who become pregnant using a given method during the first year,[25] and sometimes as a lifetime failure rate among methods with high effectiveness, such as tubal ligation.[26]
避孕措施
避孕措施包括屏障法、賀爾蒙類避孕措施、子宮內避孕器、結紮、以及性行為控制法。這些措施是在性行為之前或性行為當中使用，而事後避孕措施則在性行為後數天仍有避孕效果。避孕成效的定義是使用該避孕方法後的第一年懷孕率。有時候也反應成功率很高的避孕方法的終身失敗率，像是結紮手術。
The most effective methods are those that are long acting and do not require ongoing health care visits.[27] Surgical sterilization, implantable hormones, and intrauterine devices all have first-year failure rates of less than 1%.[21] Hormonal contraceptive pills, patches or vaginal rings, and the lactational amenorrhea method (LAM), if used strictly, can also have first-year (or for LAM, first-6-month) failure rates of less than 1%.[27] With typical use first-year failure rates are considerably high, at 9%, due to incorrect usage.[21] Other methods such as condoms, diaphragms, and spermicides have higher first-year failure rates even with perfect usage.[27] The American Academy of Pediatrics recommends long acting reversible birth control as first line for young people.[28]
最有效的避孕措施是長效型且不需要持續回診追蹤的避孕措施。長效型避孕措施如手術結紮術、皮下植入型賀爾蒙避孕棒，以及子宮內避孕器的第一年避孕失敗率皆小於1%。若嚴格使用賀爾蒙口服避孕藥、賀爾蒙貼片、陰道內避孕環、和泌乳停經法，也可以讓第一年的避孕失敗率小於1%（使用泌乳停經法則是前六個月的避孕失敗率小於1%）。當以上避孕措施是採取典型使用時，第一年的避孕失敗率高達9%，原因是不正確的使用方式。其他避孕措施像是保險套、避孕隔膜、殺精劑，即便在採取完美使用時，皆有較高的第一年避孕失敗率。美國小兒科醫學會建議，長效可逆的避孕措施是年輕族群的第一線避孕方法。
While all methods of birth control have some potential adverse effects, the risk is less than that of pregnancy.[27] After stopping or removing many methods of birth control, including oral contraceptives, IUDs, implants and injections, the rate of pregnancy during the subsequent year is the same as for those who used no birth control.[29]
雖然所有的避孕措施皆有一些潛在的副作用，但這些風險比懷孕帶來的風險還低。當停止或移除許多避孕的措施，像是口服避孕藥、子宮內避孕器、皮下植入避孕棒、或賀爾蒙注射劑，未來一年的懷孕率和沒有使用避孕措施的人的懷孕率是一樣的。
For individuals with specific health problems, certain forms of birth control may require further investigations.[30] For women who are otherwise healthy, many methods of birth control should not require a medical exam—including birth control pills, injectable or implantable birth control, and condoms.[31] For example, a pelvic exam, breast exam, or blood test before starting birth control pills does not appear to affect outcomes.[32][33] In 2009, the World Health Organization (WHO) published a detailed list of medical eligibility criteria for each type of birth control.[30]
對於有特定健康問題的人，在使用一些避孕措施前可能需要進一步的檢查。對於健康的女性，許多避孕措施不需要健康檢查就可開始使用，像是口服避孕藥、賀爾蒙注射劑、皮下植入避孕棒、和保險套。舉例而言，在開始使用口服避孕藥前進行骨盆腔檢查、乳房檢查、或血液檢查，並不會影響使用成效。2009年世界衛生組織公布了一系列各種避孕措施的適用醫學標準。
Hormonal[edit]
Hormonal contraception is available in a number of different forms, including oral pills, implants under the skin, injections, patches, IUDs and a vaginal ring. They are currently available only for women, although hormonal contraceptives for men have and are being clinically tested.[34] There are two types of oral birth control pills, the combined oral contraceptive pills (which contain both estrogen and a progestogen) and the progestogen-only pills (sometimes called minipills).[35] If either is taken during pregnancy, they do not increase the risk of miscarriage nor cause birth defects.[33] Both types of birth control pills prevent fertilization mainly by inhibiting ovulation and thickening cervical mucous.[36][37] Their effectiveness depends on the user remembering to take the pills.[33] They may also change the lining of the uterus and thus decrease implantation.[37]
賀爾蒙類避孕措施
賀爾蒙類避孕措施有許多種類型，像是口服避孕藥、皮下植入型避孕棒、注射劑、貼片、子宮內避孕器、和陰道內避孕環。這些避孕措施通常只適用於女性，不過目前適用於男性的賀爾蒙類避孕措施也開始進入臨床測試。口服避孕藥有兩種，一種是複合型口服避孕藥（包含雌激素和黃體素），另一種是只含有黃體素的口服避孕藥（有時稱為迷你避孕藥）。兩種口服避孕藥若在懷孕時服用，皆不會增加流產或胎兒先天異常的機會。兩種避孕藥預防授精的方式為抑制排卵和增加子宮頸分泌液的黏性，因而降低精子進入的機會。它們的效度取決於使用者是否記得在固定的時間服用口服避孕藥。它們也會改變子宮內膜，進而降低著床率。
Combined hormonal contraceptives are associated with a slightly increased risk of venous and arterial blood clots.[38] Venous clots, on average, increase from 2.8 to 9.8 per 10,000 women years[39] which is still less than that associated with pregnancy.[38] Due to this risk, they are not recommended in women over 35 years of age who continue to smoke.[40] Due to the increased risk they are included in decision tools such as the DASH score and PERC rule used to predict the risk of blood clots.[41]
複合型賀爾蒙避孕措施會增加發生動脈和靜脈血栓的風險。當使用複合型賀爾蒙避孕措施時，每一萬名婦女中發生靜脈血栓的平均風險從2.8位增加到9.8位，不過此數目依然低於懷孕時的靜脈血栓風險。因此，大於三十五歲並且持續抽菸的女性不建議使用複合型賀爾蒙避孕措施。因為複合型賀爾蒙避孕措施會增加血栓風險，在一些評估血栓風險的計算公式中（如DASH score和PERC rule）均將賀爾蒙的使用列入計分。
The effect on sexual desire is varied, with increase or decrease in some but with no effect in most.[42] Combined oral contraceptives reduce the risk of ovarian cancer and endometrial cancer and do not change the risk of breast cancer.[43][44] They often reduce menstrual bleeding and painful menstruation cramps.[33] The lower doses of estrogen released from the vaginal ring may reduce the risk of breast tenderness, nausea, and headache associated with higher dose estrogen products.[43]
賀爾蒙避孕措施對性慾的影響因人而異。大部分人的性慾不會受到影響，而在一些人的性慾會因其增加或降低。複合型口服避孕藥會降低卵巢癌和子宮內膜癌的風險，且不會改變乳癌的發生風險。賀爾蒙避孕措施常會減少月經血量和經痛的發生。和含有高劑量雌激素賀爾蒙避孕措施相比，從陰道內避孕環釋放的低劑量雌激素會降低乳房脹痛、噁心、和頭痛的症狀。
Progestin-only pills, injections and intrauterine devices are not associated with an increased risk of blood clots and may be used by women with previous blood clots in their veins.[38][45] In those with a history of arterial blood clots, non-hormonal birth control or a progestin-only method other than the injectable version should be used.[38] Progestin-only pills may improve menstrual symptoms and can be used by breastfeeding women as they do not affect milk production. Irregular bleeding may occur with progestin-only methods, with some users reporting no periods.[46] The progestins drospirenone and desogestrel minimize the androgenic side effects but increase the risks of blood clots and are thus not first line.[47] The perfect use first-year failure rate of the injectable progestin, Depo-Provera, is 0.2%; the typical use first failure rate is 6%.[21]
僅含黃體素的口服避孕藥、賀爾蒙注射劑（Depo provera）、和子宮內避孕器不會增加血栓的發生風險，因此可以使用於曾經有過靜脈血栓病史的女性。至於曾經有過動脈血栓病史的女性則只能使用不含賀爾蒙的避孕措施或使用僅含黃體素的避孕措施（賀爾蒙注射劑［Depo Provera］除外）。僅含黃體素的口服避孕藥可以改善經期時的症狀，也可以使用於哺乳時的女性，因為不會減少母乳的分泌。當使用僅含黃體素的口服避孕藥時可能會發生不規則陰道出血的症狀，一些使用者甚至會出現無月經的情形。兩種黃體素drospirenone和desogestrel雖然會減少雄性性徵的副作用，但會增加血栓的風險，因此不是避孕措施中的第一線用藥。賀爾蒙注射劑（Depo Provera）在採取完美使用時的第一年失敗率是0.2%，而在採取典型使用時的第一年失敗率則是6%。
Birth control pills
口服避孕藥
A transdermal contraceptive patch
經皮吸收的避孕貼片
A NuvaRing vaginal ring
陰道避孕環 NuvaRing
Barrier contraceptives are devices that attempt to prevent pregnancy by physically preventing sperm from entering the uterus.[42] They include male condoms, female condoms, cervical caps, diaphragms, and contraceptive sponges with spermicide.[42]
屏障法
屏障避孕措施是利用物理性阻隔的方式預防精子進入子宮，以達到避孕的效果，種類包括男用保險套、女用保險套、子宮頸帽、避孕隔膜、以及含有殺精劑的避孕海綿。
Globally, condoms are the most common method of birth control.[49] Male condoms are put on a man’s erect penis and physically block ejaculated sperm from entering the body of a sexual partner.[50] Modern condoms are most often made from latex, but some are made from other materials such as polyurethane, or lamb’s intestine.[50] Female condoms are also available, most often made of nitrile, latex or polyurethane.[51] Male condoms have the advantage of being inexpensive, easy to use, and have few adverse effects.[52]Making condoms available to teenagers does not appear to affect the age of onset of sexual activity or its frequency.[53] In Japan about 80% of couples who are using birth control use condoms, while in Germany this number is about 25%,[54] and in the United States it is 18%.[55]
全世界最普遍使用的避孕措施是保險套。男用保險套的使用方式是套在勃起的陰莖上，物理性的阻擋射出的精子進入性交對象的體內。現代的保險套的製作材料大多是乳膠（英語：latex），但也有保險套是利用其他材料製作而成，像是聚胺酯（英語：polyurethane）或是羊腸衣。另外也有女用保險套，最常使用的製作材料是nitrile、乳膠、和聚胺酯。男用保險套的優點是便宜、容易使用，和少有副作用。讓青少年容易取得保險套並不會改變開始發生性行為的年紀或發生性行為的頻率。在日本約80%的伴侶是使用保險套作為避孕的方式；在德國是約25%，而在美國則是18%使用保險套避孕。
Male condoms and the diaphragm with spermicide have typical use first-year failure rates of 18% and 12%, respectively.[21]With perfect use condoms are more effective with a 2% first-year failure rate versus a 6% first-year rate with the diaphragm.[21] Condoms have the additional benefit of helping to prevent the spread of some sexually transmitted infections such as HIV/AIDS.[5]
在典型使用下，男用保險套的第一年失敗率為18%；避孕隔膜和殺精劑則為12%。在完美使用時，保險套的第一年失敗率為2%。相較於完美使用下第一年失敗率為6%的避孕隔膜，保險套的避孕效果更為有效。此外，保險套還有能防止性病傳播的優點（如愛滋病）。
Contraceptive sponges combine a barrier with a spermicide.[27] Like diaphragms, they are inserted vaginally before intercourse and must be placed over the cervix to be effective.[27] Typical failure rates during the first year depend on whether or not a woman has previously given birth, being 24% in those who have and 12% in those who have not.[21] The sponge can be inserted up to 24 hours before intercourse and must be left in place for at least six hours afterward.[27]Allergic reactions[56] and more severe adverse effects such as toxic shock syndrome have been reported.[57]
避孕海綿是一層含有殺精劑的屏障。使用方法和避孕隔膜一樣，在性行為前置入陰道，並且要放置在子宮頸前方才能達到避孕的效果。典型使用下的第一年失敗率取決於女性是否有過陰道自然產，從未生產過的女性的第一年失敗率為12%，而生產過的女性則為24%。避孕海綿可以在性行為前最多24小時內置入陰道，並且需在性行為後留置在陰道中至少六小時。因為使用避孕海綿導致過敏反應和嚴重的副作用（像是中毒性休克症候群）皆曾被報導過。
捲起的男用保險套
展開的男用保險套
聚胺酯成分的女用保險套
A diaphragm vaginal-cervical barrier, in its case with a quarter U.S. coin.
置放在盒子中的避孕隔膜，以及一枚美金25分硬幣
A contraceptive sponge set inside its open package.
置放在已開封的包裝中的避孕海綿
子宮內避孕器
The current intrauterine devices (IUD) are small devices, often ’T’-shaped, often containing either copper or levonorgestrel, which are inserted into the uterus. They are one form of long-acting reversible contraception which are the most effective types of reversible birth control.[58] Failure rates with the copper IUD is about 0.8% while the levonorgestrel IUD has a failure rates of 0.2% in the first year of use.[59]Among types of birth control, they along with birth control implants result in the greatest satisfaction among users.[60] As of 2007, IUDs are the most widely used form of reversible contraception, with more than 180 million users worldwide.[61]
目前市場上的[[子宮環|子宮內避孕器]]（IUD）皆為體積小、T型的裝置，使用方法為置入子宮內，通常含有銅或是人工合成黃體素（如levonorgestrel）的成分。子宮內避孕器屬於{{le|長效型可逆避孕措施|Long-acting_reversible_contraception}}的一種，而長效型可逆避孕措施在所有可逆型避孕方法中的避孕效果最好[58]。銅T子宮內避孕器的第一年失敗率為0.8%，而黃體素子宮內避孕器則為0.2%[59]。在所有的避孕方法中，子宮內避孕器和皮下植入避孕棒擁有最高的使用者滿意度[60]。2007年中，可逆型避孕方法中使用率最高的就是子宮內避孕器，在全世界有一億八千萬的使用者[61]。
Evidence supports effectiveness and safety in adolescents[60] and those who have and have not previously had children.[62]IUDs do not affect breastfeeding and can be inserted immediately after delivery.[63] They may also be used immediately after an abortion.[64] Once removed, even after long term use, fertility returns to normal immediately.[65]
對青少年以及已生育小孩或未生育小孩的女性而言，研究指出使用子宮內避孕器既安全，且能達到有效的避孕效果[60][62]。子宮內避孕器不會對[[哺乳]]造成影響，並且可以在生產後立刻置入子宮[63]。此外，子宮內避孕器也可以在[[墮胎]]後立刻置入[64]。即使曾長期使用子宮內避孕器，在移除後也能立即恢復生育能力[65]。
While copper IUDs may increase menstrual bleeding and result in more painful cramps[66] hormonal IUDs may reduce menstrual bleeding or stop menstruation altogether.[63] Cramping can be treated with NSAIDs.[67] Other potential complications include expulsion (2–5%) and rarely perforation of the uterus (less than 0.7%).[63][67] A previous model of the intrauterine device (the Dalkon shield) was associated with an increased risk of pelvic inflammatory disease, however the risk is not affected with current models in those without sexually transmitted infections around the time of insertion.[68]
銅T子宮內避孕器容易造成使用的女性經血量過多，並讓經痛更為嚴重。而賀爾蒙子宮內避孕器則會減少經血量，甚至月經停止。舉例而言，在使用Mirena子宮內避孕器一年後，有20%的女性會發生月經停止的現象。使用NSAIDs類藥物可以使經痛獲得改善。其他潛在的副作用包括子宮內避孕器脫出子宮(2-5%)，以及罕見的穿出子宮(少於0.7%)。
早期的子宮內避孕器模型 Dalkon Shield 會增加骨盆腔感染的風險。至於現階段的子宮內避孕器，若在置入前後沒有感染性病，骨盆腔感染的機率不會因置入子宮內避孕器而增加。
絕育 Sterilization
Surgical sterilization is available in the form of tubal ligation for women and vasectomy for men.[2] There are no significant long-term side effects, and tubal ligation decreases the risk of ovarian cancer.[2] Short term complications are twenty times less likely from a vasectomy than a tubal ligation.[2][69] After a vasectomy, there may be swelling and pain of the scrotum which usually resolves in a week or two.[70] With tubal ligation, complications occur in 1 to 2 percent of procedures with serious complications usually due to the anesthesia.[71] Neither method offers protection from sexually transmitted infections.[2]
絕育手術包含女性的輸卵管結紮手術和男性的輸精管結紮手術。兩種手術並無長期併發症，且輸卵管結紮手術可以減少特定種類的卵巢癌的發生機會。就短期併發症而言，輸精管結紮手術的短期併發症比輸卵管阻斷術低了20倍。接受輸精管結紮手術後，可能會有陰囊腫脹和疼痛的症狀，大部分會在一到兩個禮拜後改善。而輸卵管結紮手術中，1-2%的手術會發生嚴重併發症，原因通常和麻醉相關。而兩種結紮手術皆無法預防性病的傳染。
This decision may cause regret in some men and women. Of women aged over 30 who have undergone tubal ligation, about 5% regret their decision, as compared with 20% of women aged under 30.[2] By contrast, less than 5% of men are likely to regret sterilization. Men more likely to regret sterilization are younger, have young or no children, or have an unstable marriage.[72] In a survey of biological parents, 9% stated they would not have had children if they were able to do it over again.[73]
一些接受過結紮手術的男性和女性的確可能會後悔。在超過30歲、接受過輸卵管結紮手術的女性中，有5%的女性後悔接受結紮手術。相較之下，小於30歲的女性在接受輸卵管結紮手術後，有20%感到後悔。相反的，小於5%的男性對於輸精管結紮手術的決定感到後悔。會後悔接受結紮手術的男性通常比較年輕、有年紀小的小孩或甚至沒有小孩，或者婚姻關係不穩定。
Although sterilization is considered a permanent procedure,[74] it is possible to attempt a tubal reversal (輸卵管重建術) to reconnect the fallopian tubes (輸卵管) or a vasectomy reversal (輸精管重建術) to reconnect the vasa deferentia (輸精管). In women the desire for a reversal is often associated with a change in spouse.[74] Pregnancy success rates after tubal reversal are between 31 and 88 percent, with complications including an increased risk of ectopic pregnancy (子宮外孕).[74] The number of males who request reversal is between 2 and 6 percent.[75] Rates of success in fathering another child after reversal are between 38 and 84 percent; with success being lower the longer the time period between the original procedure and the reversal.[75] Sperm extraction (取精術) followed by in vitro fertilization (體外人工受精) may also be an option in men.[76]
雖然結紮手術被認為是一項不可逆的手術，但在特定輸卵管手術中，還是有可能透過輸卵管重建術重先連結切斷的輸卵管；或是透過輸精管重建術，重新連接切斷的輸精管。在想要接受輸卵管重建手術的女性中，手術原因通常和變換伴侶有關。輸卵管重建手術後的懷孕率約在 31%至88% 不等，但會增加 [[子宮外孕]]等併發症的機會[74]。想要進行輸精管重建術的男性約佔2-6%，術後讓伴侶成功受孕的機率在38%至84% 不等。若輸精管結紮術和重建術之間相隔的時間越長，術後讓伴侶成功受孕的機率則會越低[˙75]。若希望在輸精管結紮術後生育小孩，另一種作法是透過{{le|取精術| Sperm extraction}}取得精子，再進行[[體外人工受精]][69]。
Behavioral 行為避孕法
Behavioral methods involve regulating the timing or method of intercourse to prevent introduction of sperm into the female reproductive tract, either altogether or when an egg may be present.[77] If used perfectly the first-year failure rate may be around 3.4%, however if used poorly first-year failure rates may approach 85%.[78]
計算性交的時間點讓精子和卵子無法相遇，或是改變性交的方式，避免讓精子進入女性生殖系統中，皆屬於行為避孕法。若正確使用行為避孕法，第一年失敗率約3.4%，但若無法正確使用，第一年失敗率可能高達85%。
Fertility awareness 排卵期避孕法
Fertility awareness methods involve determining the most fertile days of the menstrual cycle and avoiding unprotected intercourse.[77]Techniques for determining fertility include monitoring basal body temperature, cervical secretions, or the day of the cycle.[77] They have typical first-year failure rates of 24%; perfect use first-year failure rates depend on which method is used and range from 0.4% to 5%.[21]The evidence on which these estimates are based, however, is poor as the majority of people in trials stop their use early.[77] Globally, they are used by about 3.6% of couples.[79] If based on both basal body temperature and another primary sign, the method is referred to as symptothermal. Overall first-year failure rates of <2% to 20% have been reported in clinical studies of the symptothermal method.[80][81]
排卵期避孕法是避開在生理週期中最容易受孕的日子進行無避孕措施的性行為，方法像是監控基礎體溫、子宮頸黏液、還有生理週期日子等等。當典型使用排卵期避孕法時，第一年失敗率為24%。若是完美使用排卵期避孕法，不同避孕法的第一年失敗率約在0.4%到5%之間。不過在排卵期避孕法的相關研究中，大部分受試人都提早終止使用排卵期避孕法，因此相關研究的統計數字的可信度很低。全世界使用排卵期避孕法的伴侶約有3.6%。若單純使用基礎體溫以及其他排卵相關徵狀作為避孕的依據，則稱為徵狀基礎體溫法。臨床研究指出，徵狀基礎體溫法的第一年失敗率約在小於2%到20%之間。
Withdrawal 體外射精法
The withdrawal method (also known as coitus interruptus) is the practice of ending intercourse ("pulling out") before ejaculation.[82] The main risk of the withdrawal method is that the man may not perform the maneuver correctly or in a timely manner.[82] First-year failure rates vary from 4% with perfect usage to 22% with typical usage.[21] It is not considered birth control by some medical professionals.[27]
There is little data regarding the sperm content of pre-ejaculatory fluid.[83] While some tentative research did not find sperm,[83] one trial found sperm present in 10 out of 27 volunteers.[84] The withdrawal method is used as birth control by about 3% of couples.[79]
體外射精法又稱之為性交中斷法，是在射精之前停止性交（拔出）的避孕法。這個避孕法最大的風險是男性可能無法正確的使用此方法，或是無法在正確的時間點拔出。第一年失敗率的範圍可以從完美使用的4%到典型使用的22%。對於一些醫療專業人員而言，體外射精法不屬於避孕的一種。
探討精液中的精子含量的相關研究很少。有些嘗試性的研究指出精液中不存在精子，但在一項研究中卻發現在27名自願受試者中，有10位受試者的精液中存在精子。約有3%的伴侶是使用體外射精法進行避孕。
禁慾 Abstinence
Though some groups advocate total sexual abstinence, by which they mean the avoidance of all sexual activity, in the context of birth control the term usually means abstinence from vaginal intercourse.[85][86] Abstinence is 100% effective in preventing pregnancy; however, not everyone who intends to be abstinent refrains from all sexual activity, and in many populations there is a significant risk of pregnancy from nonconsensual sex (非自願性性行為).[87][88]
雖然有些組織提倡完全{{le|禁慾 (性行為)|sexual abstinence|禁慾}}，也就是禁止各種類型的性行為，但在避孕的定義下，禁慾是指不進行陰道性行為[78][79]。禁慾可以百分之百有效的避免懷孕，但不是所有想要禁慾的人都會停止各式各樣的性行為。而在許多族群中，非自願性性行為則導致了相當高比例的懷孕[80][81]。
Abstinence-only sex education does not reduce teenage pregnancy.[7][89] Teen pregnancy rates are higher in students given abstinence-only education, as compared with comprehensive sex education.[89][90] Some authorities recommend that those using abstinence as a primary method have backup method(s) available (such as condoms or emergency contraceptive pills).[91] Deliberate non-penetrative sex without vaginal sex or deliberate oral sex without vaginal sex are also sometimes considered birth control.[92]While this generally avoids pregnancy, pregnancy can still occur with intercrural sex and other forms of penis-near-vagina sex (genital rubbing, and the penis exiting from anal intercourse) where sperm can be deposited near the entrance to the vagina and can travel along the vagina’s lubricating fluids.[93][94]
單單只強調[[禁慾 (性行為)|守貞]]（[[純潔教育]]）的性教育無法降低[[未成年懷孕]]的比例[7][89]。相較於接受完整性教育的學生，只接受純潔教育的學生的懷孕率更高[89][90]。有些專家建議，使用禁慾做為主要的避孕方式則須有備用的避孕方案（例如保險套或是事後避孕藥）[91]。謹慎的進行不包含陰道性交的[[非插入式性行為]]或是[[口交]]]，有時也被認為是一種避孕的方式[85]。雖然這些方法通常能防止懷孕，[[股間性交]]或是其他陰莖接近陰道的性行為（例如性器磨擦、或是[[肛交]]後將陰莖拔出）還是可能會導致懷孕。這些行為會讓精子接近陰道口，透過陰道分泌的潤滑液游入陰道，因此仍有懷孕的風險[86][87]。
泌乳停經法 Lactation
The lactational amenorrhea method(泌乳停經法 ⎘) involves the use of a woman’s natural postpartum infertilitywhich(母乳哺育 ⎘) occurs after delivery and may be extended by breastfeeding(母乳哺育 ⎘).[88] This usually requires the presence of no periods(月經 ⎘), exclusively breastfeeding the infant, and a child younger than six months.[22] The World Health Organization(世界卫生组织 ⎘) states that if breastfeeding is the infant’s only source of nutrition, the failure rate is 2% in the six months following delivery.[89] Six uncontrolled studies of lactational amenorrhea method users found failure rates at 6 months postpartum between 0% and 7.5%.[90] Failure rates increase to 4–7% at one year and 13% at two years.[91] Feeding formula, pumping instead of nursing, the use of a pacifier(奶嘴 ⎘), and feeding solids all increase its failure rate.[92] In those who are exclusively breastfeeding, about 10% begin having periods before three months and 20% before six months.[91] In those who are not breastfeeding, fertility may return four weeks after delivery.[91]
[[泌乳停經法]]是在產婦分娩後，利用[[母乳哺育]]的方式來延後排卵的時間[88]。會有一段期間沒有[[月經]]。此方式適合於為新生兒及不到六個月的嬰兒哺乳情形[22]。[[世界衛生組織]]表示若這段時間母乳是嬰兒唯一的營養來源，產後六個月的避孕失效率只有2%[89]。有六個無控制組的，針對使用泌乳停經法避孕的研究，產後六個月都使用泌乳停經法，避孕失效率從0%到7.5%不等[90]。若繼續使用到產後一年，失效率為4-7%，若繼續使用到產後二年，失效率為13%[91]。餵食配方奶、先將母奶擠出再用奶瓶餵小孩、使用[[奶嘴]]或是餵食固體副食品都會增加失效率[92]。<!--In those who are exclusively breastfeeding, about 10% begin having periods before three months and 20% before six months.[91]-->若是沒有哺乳的產婦，約在分娩後四週會恢復生育能力[91]。
Emergency
Emergency contraceptive(紧急避孕 ⎘) methods are medications (sometimes misleadingly referred to as "morning-after pills")[93]or devices used after unprotected sexual intercourse with the hope of preventing pregnancy.[94] They work primarily by preventing ovulation or fertilization.[6] A number of options exist, including high dose birth control pills, levonorgestrel(左炔诺孕酮 ⎘), mifepristone(美服培酮 ⎘), ulipristal and IUDs.[95] Levonorgestrelpills(左炔诺孕酮 ⎘), when used within 3 days, decrease the chance of pregnancy after a single episode of unprotected sex or condom failure by 70% (resulting in a pregnancy rate of 2.2%).[94] Ulipristal, when used within 5 days, decreases the chance of pregnancy by about 85% (pregnancy rate 1.4%) and might be a little more effective than levonorgestrel.[94][95][96] Mifepristoneis(美服培酮 ⎘) also more effective than levonorgestrel while copper IUDs are the most effective method.[95] IUDs can be inserted up to five days after intercourse and prevent about 99% of pregnancies after an episode of unprotected sex (pregnancy rate of 0.1 to 0.2%).[6][97] This makes them the most effective form of emergency contraceptive.[98] In those who are overweight(超重 ⎘) or obese(肥胖症 ⎘) levonorgestrel is less effective and an IUD or ulipristal is recommended.[99]
Providing emergency contraceptive pills to women in advance does not affect rates of sexually transmitted infections, condom use, pregnancy rates, or sexual risk-taking behavior.[100][101] All methods have minimal side effects.[95]
Dual protection is the use of methods that prevent both sexually transmitted infections and pregnancy.[102]This can be with condoms either alone or along with another birth control method or by the avoidance of penetrative sex(性交 ⎘).[103][104] If pregnancy is a high concern using two methods at the same time is reasonable,[103]and two forms of birth control is recommended in those taking the anti-acne(粉刺 ⎘) drug isotretinoin(異維A酸 ⎘), due to the high risk of birth defects(先天性障碍 ⎘) if taken during pregnancy.[105]
Effects
Health
Maternal mortality rate as of 2010[106]
Contraceptive use in developing countries(发展中国家 ⎘) is estimated to have decreased the number of maternal deaths(孕产妇死亡 ⎘) by 40% (about 270,000 deaths prevented in 2008) and could prevent 70% of deaths if the full demand for birth control were met.[15][16]These benefits are achieved by reducing the number of unplanned pregnancies that subsequently result in unsafe abortions and by preventing pregnancies in those at high risk.[15]
Birth control also improves child survival in the developing world by lengthening the time between pregnancies.[15] In this population, outcomes are worse when a mother gets pregnant within eighteen months of a previous delivery.[15][107] Delaying another pregnancy after a miscarriage(流产 ⎘) however does not appear to alter risk and women are advised to attempt pregnancy in this situation whenever they are ready.[107]
Teenage pregnancies(未成年懷孕 ⎘), especially among younger teens, are at greater risk of adverse outcomes including early birth(早產 ⎘), low birth weight, and death of the infant(婴儿死亡率 ⎘).[10] In the United States 82% of pregnancies in those between 15 and 19 are unplanned.[60] Comprehensive sex education(性教育 ⎘) and access to birth control are effective in decreasing pregnancy rates in this age group.[108]
Finances
Countries by fertility rateas(总和生育率 ⎘) of 2012.
7–8 Children
6–7 Children
5–6 Children
4–5 Children
3–4 Children
2–3 Children
1–2 Children
0–1 Children
In the developing world, birth control increases economic growth(经济增长 ⎘) due to there being fewer dependent children and thus more women participating in the workforce(劳动力 ⎘).[17]Women’s earnings, assets, body mass index(身高體重指數 ⎘), and their children’s schooling and body mass index all improve with greater access to birth control.[17] Family planning(计划生育 ⎘) via the use of modern birth control is one of the most cost-effective health interventions.[109] For every dollar spent, the United Nations estimates that two to six dollars are saved.[110] These cost savings are related to preventing unplanned pregnancies and decreasing the spread of sexually transmitted illnesses.[109] While all methods are beneficial financially, the use of copper IUDs resulted in the greatest savings.[109]
The total medical cost for a pregnancy, delivery and care of a newborn in the United States is on average $21,000 for a vaginal delivery and $31,000 for a Caesarean section(剖宫产 ⎘) as of 2012.[111] In most other countries the cost is less than half.[111] For a child born in 2011, an average US family will spend $235,000 over 17 years to raise them.[112]
Prevalence
Percentage of women using modern birth control as of 2010.
6%
12%
18%
24%
30%
36%
42%
48%
54%
60%
66%
72%
78%
84%
86%
No data
Globally, as of 2009, approximately 60% of those who are married and able to have children use birth control.[113] How frequently different methods are used varies widely between countries.[113]The most common method in the developed world is condoms and oral contraceptives, while in Africa it is oral contraceptives and in Latin America and Asia it is sterilization.[113] In the developing world overall, 35% of birth control is via female sterilization, 30% is via IUDs, 12% is via oral contraceptives, 11% is via condoms, and 4% is via male sterilization.[113]
While less used in the developed countries than the developing world, the number of women using IUDs as of 2007 was more than 180 million.[54] Avoiding sex when fertile is used by about 3.6% of women of childbearing age, with usage as high as 20% in areas of South America.[114] As of 2005, 12% of couples are using a male form of birth control (either condoms or a vasectomy) with higher rates in the developed world.[115] Usage of male forms of birth control has decreased between 1985 and 2009.[113] Contraceptive use among women in Sub-Saharan Africa(撒哈拉以南非洲 ⎘) has risen from about 5% in 1991 to about 30% in 2006.[116]
As of 2012, 57% of women of childbearing age want to avoid pregnancy (867 of 1520 million).[117] About 222 million women however were not able to access birth control, 53 million of whom were in sub-Saharan Africa and 97 million of whom were in Asia.[117]This results in 54 million unplanned pregnancies and nearly 80,000 maternal deaths a year.[113] Part of the reason that many women are without birth control is that many countries limit access due to religious or political reasons,[6] while another contributor is poverty(貧窮 ⎘).[118] Due to restrictive abortion(堕胎 ⎘) laws in Sub-Saharan Africa, many women turn to unlicensed abortion providers for unintended pregnancy, resulting in about 2–4% obtaining unsafe abortions each year.[118]
History
Early history
Ancient silver coin from Cyrene(昔兰尼 ⎘) depicting a stalk of silphium
The Egyptian Ebers Papyrus from 1550 BCE and the Kahun Papyrus from 1850 BCE have within them some of the earliest documented descriptions of birth control: the use of honey, acacia leaves and lint to be placed in the vagina to block sperm.[119][120]It is believed that in Ancient Greece(古希腊 ⎘) silphium was used as birth control which, due to its effectiveness and thus desirability, was harvested into extinction.[121]
In medieval Europe, any effort to halt pregnancy was deemed immoral by the Catholic Church(天主教會 ⎘),[119] although it is believed that women of the time still used a number of birth control measures, such as coitus interruptus(体外排精 ⎘) and inserting lily root and rue into the vagina (and, in addition, infanticide after birth).[122] Casanova(贾科莫·卡萨诺瓦 ⎘), living in 18th century Italy(意大利 ⎘), described the use of a lambskin covering to prevent pregnancy; however, condoms only became widely available in the 20th century.[119]
Birth control movement[edit source]
"And the villain still pursues her", a satirical Victorian era(维多利亚时代 ⎘) postcard
The birth control movement developed during the 19th and early 20th centuries.[123] The Malthusian League, based on the ideas of Thomas Malthus(托马斯·罗伯特·马尔萨斯 ⎘), was established in 1877 to education the public about the importance of family planning(计划生育 ⎘) and to advocate for getting rid of penalties for promoting birth control.[124] It was founded during the "Knowlton trial" of Annie BesantandCharles Bradlaugh, who were prosecuted for publishing on various methods of birth control.[125]
In the United States(美国 ⎘), Margaret Sanger(山額夫人 ⎘) and Otto Bobsein popularized the phrase "birth control" in 1914.[126][127]Sanger was mainly active in the United States but had gained an international reputation by the 1930s. Sanger established a short-lived birth-control clinic in 1916, which was shut down after eleven days and resulted in her arrest.[128] The publicity surrounding the arrest, trial, and appeal sparked birth control activism across the United States.[129]
The first permanent birth-control clinic was established in Britain in 1921 by Marie Stopesworking with the Malthusian League.[130] The clinic, run by midwives and supported by visiting doctors,[131] offered mothers birth-control advice and taught them the use of a cervical cap(宫颈帽 ⎘). Her clinic made contraception acceptable during the 1920s by presenting it in scientific terms. Throughout the 1920s, Stopes and other feminist(女性主義 ⎘) pioneers, including Dora RussellandStella Browne, played a major role in breaking down taboos(禁忌 ⎘) about sex. In April 1930 the Birth Control Conference assembled 700 delegates and was successful in bringing birth control and abortion into the political sphere - three months later, the Ministry of Health, in the United Kingdom, allowed local authorities to give birth-control advice in welfare centers.[132]
Modern methods
In 1909, Richard Richter developed the first intrauterine device made from silkworm gut, which was further developed and marketed in Germany by Ernst Gräfenberg in the late 1920s.[133] Gregory Pincus(格雷戈里·平卡斯 ⎘) and John Rock with help from the Planned Parenthood Federation of America developed the first birth control pills in the 1950s, such as mestranol/norethynodrel, which became publicly available in the 1960s.[134] Medical abortion became an alternative to surgical abortion with the availability of prostaglandin analogs in the 1970s and mifepristonein(美服培酮 ⎘) the 1980s.[135]
社會與文化 Society and culture
Legal positions
Human rights(人权 ⎘) agreements require most governments to provide family planning and contraceptive information and services. These include the requirement to create a national plan for family planning services, remove laws that limit access to family planning, ensure that a wide variety of safe and effective birth control methods are available including emergency contraceptives, make sure there are appropriately trained healthcare providers and facilities at an affordable price, and create a process to review the programs implemented. If governments fail to do the above it may put them in breach of binding international treaty obligations.[136]
In 2010, the United Nations launched the Every Woman Every Child movement to assess the progress toward meeting women’s contraceptive needs. The initiative has set a goal of increasing the number of users of modern birth control by 120 million women in the world’s 69 poorest countries by the year 2020. Additionally, they aim to eradicate discrimination against girls and young women who seek contraceptives.[137][138]
聯合國在2010年提出了Every Woman Every Child movement，推動符合女性避孕需求的相關政策及措施。此一計劃的目標是在2020年前使世界上最貧窮69個國家之中的1.2億女性，可以有更多人可以使用現代的避孕方式。此外，也希望可以消除對於想要避孕的女孩以及年輕女性的歧視。
(台灣知識種子計畫粉專 醫週譯小時支援前線活動 by Chris Cheng-Hui Chang)
宗教觀點 Religious views
Main article: Religion and birth control
Religions vary widely in their views of the ethics(伦理学 ⎘) of birth control.[139] The Roman Catholic Church(天主教會 ⎘) officially only accepts natural family planning in certain cases,[140] although large numbers of Catholics in developed countries(已開發國家 ⎘) accept and use modern methods of birth control.[141][142][143] Among Protestants(新教 ⎘) there is a wide range of views from supporting none to allowing all methods of birth control.[144] Views in Judaism(犹太教 ⎘) range from the stricter Orthodox(猶太教正統派 ⎘) sect to the more relaxed Reform(猶太教改革派 ⎘) sect.[145] Hindus(印度教 ⎘) may use both natural and artificial contraceptives.[146]A common Buddhist(佛教 ⎘) view is that preventing conception is acceptable, while intervening after conception has occurred is not.[147]
In Islam(伊斯兰教 ⎘), contraceptives are allowed if they do not threaten health, although their use is discouraged by some.[148] The Quran(古兰经 ⎘) does not make any explicit statements about the morality of birth control, but contains statements encouraging having children(繁殖 ⎘). Prophet Muhammadalso(穆罕默德 ⎘) is reported to have said "marry and procreate".[149]
各宗教對於避孕的觀點差異很大[139]。[[天主教會]]基本上只接受{{le|自然計劃生育|Natural family planning}}，也就是用配合女性的月經，只在不會受孕的時間進行性行為的避孕方式，不接受包括保險套在內的其他人工避孕方式，不過許多[[開發中國家]]的天主教教會會接受及使用現代的避孕方式[141][142][143]。基督教[[新教]]的觀點從完全不接受人工避孕方式（{{le|Quiverfull|Quiverfull}}）到接受所有的避孕方式[144]，不過有關受精後中止懷孕的部份，因為威脅生命，仍有相當爭議。[[猶太教]]的觀點也隨教派有差異，[[猶太教正統派]]的限制較多，[[猶太教改革派]]就沒有那麼多限制[145]。[[印度教]]用自然及人工的避孕方式[146]。[[佛教]]的常見觀點是接受避免受精卵產生的避孕方式，但是不接受受精後中止懷孕的避孕方式[147]。
[[伊斯蘭教]]中，若避孕本身不會威脅生命，是可被允許的，不過多半是不鼓勵[148]。[[古蘭經]]沒有針對避孕的道德層面有直接具體的說明，不過有內容鼓勵[[繁殖|多多生育子女]]，其中也提到先知[[穆罕默德]]"結婚而且生育"[149]。
世界避孕日 World Contraception Day
The 26th of September is World Contraception Day, devoted to raising awareness and improving education about sexual and reproductive health, with a vision of a world where every pregnancy is wanted.[150] It is supported by a group of governments and international NGOs, including the Asian Pacific Council on Contraception, Centro Latinamericano Salud y Mujer, the European Society of Contraception and Reproductive Health, the German Foundation for World Population, the International Federation of Pediatric and Adolescent Gynecology, International Planned Parenthood Federation(国际计划生育联合会 ⎘), the Marie Stopes International, Population Services International, the Population Council, the United States Agency for International Development(美国国际开发署 ⎘) (USAID), and Women Deliver.[150]
為了讓大眾提高避孕意識、促進性教育及生殖健康教育，因此將9月26日定為世界避孕日，其願景是「一個所有懷孕都是被期待的世界。」[150]</ref>有許多的國際組織支持此一活動，包括：亚太避孕理事会（Asian Pacific Council on Contraception）、拉丁美洲衛生和婦女中心（Centro Latinamericano Salud y Mujer）、歐洲避孕及生殖健康協會（European Society of Contraception and Reproductive Health）、{{le|德国世界人口基金会|German Foundation for World Population}}、國際兒童及青春期婦科聯合會（International Federation of Pediatric and Adolescent Gynecology） 、[[国际计划生育联合会]]（International Planned Parenthood Federation）、{{le|玛丽斯特普国际组织|Marie Stopes International}}、{{le|国际人口服务组织|Population Services International}}、{{le|人口理事会|Population Council}}、[[美国国际开发署]]（USAID）、{{le|Women Deliver|Women Deliver}}[150]。
Misconceptions
There are a number of common misconceptions(常見錯誤觀念列表 ⎘) regarding sex and pregnancy.[151] Douching after sexual intercourse is not an effective form of birth control.[152]Additionally, it is associated with a number of health problems and thus is not recommended.[153] Women can become pregnant the first time they have sexual intercourse[154] and in any sexual position(性交体位 ⎘).[155] It is possible, although not very likely, to become pregnant during menstruation.[156]
研究方向 Research directions
Females
Improvements of existing birth control methods are needed, as around half of those who get pregnant unintentionally are using birth control at the time.[25] A number of alterations of existing contraceptive methods are being studied, including a better female condom, an improved diaphragm, a patch containing only progestin, and a vaginal ring containing long-acting progesterone.[157] This vaginal ring appears to be effective for three or four months and is currently available in some areas of the world.[157]
A number of methods to perform sterilization via the cervix are being studied. One involves putting quinacrine in the uterus which causes scarring and infertility. While the procedure is inexpensive and does not require surgical skills, there are concerns regarding long-term side effects.[158] Another substance, polidocanol, which functions in the same manner is being looked at.[157] A device called Essure, which expands when placed in the fallopian tubes and blocks them, was approved in the United States in 2002.[158]
接近一半使用避孕措施的婦女意外懷孕， 因此現行避孕方法需要改進[25]。目前改良已有避孕措施的研究包括：改良的女性保險套、改良的避孕隔膜、僅含黃體素的口服避孕藥，以及含有效力更久的黃體酮之陰道避孕環[157]。上述之陰道避孕環在部分國家被應用，有效期為三至四個月[157]。
另有進行針對子宮頸做避孕措施的研究，譬如把奎納克林放進子宮刺激疤痕生長導致不孕[158]。雖然這避孕措施優勢是低成本和不需要外科手術技能，但有長期使用帶來副作用的顧慮[158]。聚多卡醇的作用跟奎納克林相同[157]。在2002 年，美國通過使用Essure 體內避孕器，在輸卵管裡擴張，堵塞輸卵管[158]。
男性 Males
Methods of male birth control include condoms, vasectomies and withdrawal.[159]Between 25 and 75% of males who are sexually active would use hormonal birth control if it was available for them.[115][159] A number of hormonal and non-hormonal methods are in trials,[115] and there is some research looking at the possibility of contraceptive vaccines.[160]
A reversible surgical method under investigation is reversible inhibition of sperm under guidance(RISUG) which consists of injecting a polymer gel, styrene maleic anhydride in dimethyl sulfoxide(二甲基亞碸 ⎘), into the vas deferens(输精管 ⎘). An injection with sodium bicarbonate washes out the substance and restores fertility. Another is an intravas device which involves putting a urethane(聚氨酯 ⎘) plug into the vas deferens(输精管 ⎘) to block it. A combination of an androgen(雄激素 ⎘) and a progestin(黄体制剂 ⎘) seems promising, as do selective androgen receptor modulators.[115] Ultrasound(超聲波 ⎘) and methods to heat the testicles have undergone preliminary studies.[161]
{{main|男性避育}}
男性生育控制的方式包括保險套、輸精管切除術及體外排精法等[159]。若可以用荷爾蒙法進行避孕，有進行性行為的男性中，有25%至75%人會考慮用荷爾蒙法避孕。有一些配合荷爾蒙及不用荷爾蒙的避孕方式正在進行臨床實驗[115]，也有一些研究在評估{{le|免疫避孕|Immunocontraception}}的可行性[160]。
有一種正在研究中的可逆避孕手術為{{le|RISUG|reversible inhibition of sperm under guidance}}，其作法是注射聚合物凝膠、{{le|苯乙烯馬來酸酐|Styrene maleic anhydride}}及[[二甲基亞碸]]到[[輸精管]]中。會注射碳酸氫鈉到輸精管中，將精子沖去，維持輸精管無精子狀態。另外一種方式也是{{le|輸精管閉塞避孕|Vas-occlusive contraception}}，會將[[聚氨酯]]注射到輸精管，以阻擋精子的游動。合併[[雄激素]]及[[黄体制剂]]的避孕法正在研究中，{{le|选择性雄激素受体调节剂|selective androgen receptor modulators}}的避孕法也正在研究[115]。[[超音波]]及加熱睪丸的避孕法正在進行前期研究[161]。
Other animals
Neutering or spaying, which involves removing some of the reproductive organs, is often carried out as a method of birth control in household pets. Many animal shelters(動物收容所 ⎘) require these procedures as part of adoption agreements.[162] In large animals the surgery is known as castration(閹割 ⎘).[163] Birth control is also being considered as an alternative to hunting as a means of controlling overpopulation in wild animals.[164] Contraceptive vaccines have been found to be effective in a number of different animal populations.[165][166]
其他動物